In general, mobile communication systems have been developed to provide communication while securing mobility of users. With the rapid development of technologies, the mobile communication systems have reached a stage of providing high-speed data communication services as well as voice communication.
Currently, a standardization operation of Long Term Evolution Advanced (LTE-A) is being progressed by the 3rd Generation Partnership Project (3GPP) as one of next generation mobile communication systems. LTE-A is a technology of implementing high speed packet-based communication with a transmission rate of up to about 100 Mbps. To this end, several methods are being discussed, including a method of reducing the number of nodes located on a communication channel by simplifying a network architecture, a method of making wireless protocols closely access a wireless channel to the maximum, and the like.
Meanwhile, unlike a voice service, allocable resources of a data service are determined according to an amount of data to be transmitted and a channel status. Accordingly, a wireless communication system such as the mobile communication system manages resources such that transmission resources are allocated in consideration of an amount of resources to be transmitted by a scheduler, a channel status, and an amount of data. The management is identically implemented in LTE which is one of the next generation mobile communication systems, and a scheduler located in the BS manages and allocates wireless transmission resources.
Recently, discussion about an evolved LTE communication system (LTE-A), in which various new technologies are grafted into the LTE communication system to increase a transmission rate, is being progressed in earnest. A representative of the newly introduced technologies may be carrier aggregation. A carrier aggregation technology may use a primary carrier and one or more secondary carriers to significantly increase transmission amounts by the number of secondary carriers rather than using only one secondary carrier between a User Equipment (UE) and an evolved Node B (eNB) in the conventional communication. Meanwhile, in LTE, the primary carrier is referred to as a Primary Cell (PCell) and the secondary carrier is referred to as a Secondary Cell (SCell).
As another LTE-A technology, the standard of enhanced TDD Interference Management and Traffic Adaptation (eIMTA) is being progressed as a work item in 3GPP Rel-12. The corresponding standard is largely different from the conventional LTE TDD system in that a transmission direction of each subframe of radio frames is fixedly set to each BS in the conventional LTE TDD system but the setting can be dynamically changed in real time in the corresponding standard.